using System;
class D : IDisposable{
IDisposable a = null;
IDisposable b = null;
public void Dispose(){
using(a)
using(b)
{}
}
}
public class Test{
public static void Main(){
try{
using(D d = new D()){
Console.WriteLine("using D");
}
}
catch(Exception e){Console.WriteLine("catch");}
}
}
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